fix: rework the paginator API

Signed-off-by: Vincenzo Palazzo <[email protected]>

Author: vincenzopalazzo

common/json_param.c

@@ -1,6 +1,4 @@
-#include "ccan/tal/tal.h"
 #include "config.h"
-#include "jsmn.h"
 #include <assert.h>
 #include <bitcoin/address.h>
 #include <bitcoin/base58.h>
@@ -19,6 +17,8 @@
 #include <common/route.h>
 #include <stdbool.h>
 #include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
 
 struct param {
 	const char *name;
@@ -342,7 +342,7 @@ const char *param_subcommand(struct command *cmd, const char *buffer,
 }
 
 bool param(struct command *cmd, const char *buffer,
-	   const jsmntok_t tokens[], ...)
+	   const jsmntok_t *tokens, ...)
 {
 	struct param *params = tal_arr(tmpctx, struct param, 0);
 	const char *name;
@@ -357,15 +357,8 @@ bool param(struct command *cmd, const char *buffer,
 		if (streq(name, "")) {
 			allow_extra = true;
 			continue;
-		} else if (streq(name, "paginator")) {
-			struct command_result *result;
-			if ((result = cbx(cmd, name, buffer, NULL, arg)))
-				return result;
-			/* we allow extra but we already made a check that are
-			 * paginator keys, so this should be safe! */
-			allow_extra = true;
-			continue;
 		}
+
 		if (!param_add(&params, name, style, cbx, arg)) {
 			/* We really do ignore this return! */
 			struct command_result *ignore;
@@ -1111,23 +1104,33 @@ struct command_result *param_pubkey(struct command *cmd, const char *name,
 }
 
 struct command_result *param_paginator(struct command *cmd, const char *name,
-				       const char *buffer, const jsmntok_t *tok)
+				       const char *buffer, const jsmntok_t *tok,
+				       struct jsonrpc_paginator **paginator)
 {
-	/*
-	const jsmntok_t *tok_tmp;
-
-	tok_tmp = json_get_member(buffer, tok, "batch");
-	if (tok_tmp)
-		return NULL;
-	tok_tmp = json_get_member(buffer, tok, "offset");
-	if (tok_tmp)
+	const jsmntok_t *batch_tok, *offset_tok, *limit_tok;
+	u64 *limit, *offset;
+	const char **batch;
+
+	batch = NULL;
+	batch_tok = json_get_member(buffer, tok, "batch");
+	if (batch_tok)
+		json_to_strarr(cmd, buffer, batch_tok, &batch);
+
+	offset = tal(cmd, uint64_t);
+	offset_tok = json_get_member(buffer, tok, "offset");
+	if (offset_tok)
+		json_to_u64(buffer, offset_tok, offset);
+
+	limit = tal(cmd, uint64_t);
+	limit_tok = json_get_member(buffer, tok, "limit");
+	if (limit_tok)
+		json_to_u64(buffer, limit_tok, limit);
+
+	if (batch || (limit && offset)) {
+		*paginator = new_paginator(cmd, batch, limit, offset);
+		assert(paginator);
 		return NULL;
-
-	tok_tmp = json_get_member(buffer, tok, "limit");
-	if (tok_tmp)
-		return NULL;
-
+	}
 	return command_fail_badparam(cmd, name, buffer, tok,
-	"paginator request format in the wrong way!");*/
-	return NULL;
+				     "paginator request format in the wrong way!");
 }

common/json_param.h

@@ -88,7 +88,8 @@ enum param_style {
 
 /** Check if this is a valid paginator input */
 struct command_result *param_paginator(struct command *cmd, const char *name,
-				       const char *buffer, const jsmntok_t *tok);
+				       const char *buffer, const jsmntok_t *tok,
+	                               struct jsonrpc_paginator **paginator);
 
 /*
  * Add a required parameter.
@@ -149,7 +150,16 @@ struct command_result *param_paginator(struct command *cmd, const char *name,
 /* Special flag for 'check' which allows any parameters. */
 #define p_opt_any() "", PARAM_OPTIONAL, NULL, NULL
 
-#define p_paginator() "paginator", PARAM_OPTIONAL, param_paginator, NULL
+#define p_paginator(arg)                                           \
+	            "paginator",				   \
+	            PARAM_OPTIONAL,				   \
+		    (param_cbx)(param_paginator),                  \
+	            ({ *arg = NULL;			           \
+		    (arg) + 0*sizeof((param_paginator)((struct command *)NULL, \
+		                  (const char *)NULL,              \
+				  (const char *)NULL,              \
+				  (const jsmntok_t *)NULL,         \
+				  (arg)) == (struct command_result *)NULL); })
 
 
 /* All the helper routines. */

common/json_parse.c

@@ -711,3 +711,28 @@ json_tok_channel_id(const char *buffer, const jsmntok_t *tok,
 	return hex_decode(buffer + tok->start, tok->end - tok->start,
 			  cid, sizeof(*cid));
 }
+
+bool json_to_strarr(const tal_t *ctx, const char *buffer,
+		     const jsmntok_t *tok, const char ***arr)
+{
+	const jsmntok_t *curr;
+	size_t i;
+
+	if (tok->type != JSMN_ARRAY)
+		return false;
+
+	*arr = tal_arr(ctx, const char *, 0);
+	json_for_each_arr(i, curr, tok) {
+		struct json_escape *esc;
+		const char *str;
+
+		if (curr->type != JSMN_STRING)
+			return false;
+		esc = json_escape_string_(ctx, buffer + curr->start,
+			   curr->end - curr->start);
+		str = json_escape_unescape(ctx, esc);
+		tal_arr_expand(arr, str);
+	}
+
+	return NULL;
+}

common/json_parse.h

@@ -124,6 +124,9 @@ json_to_blinded_path(const tal_t *ctx, const char *buffer, const jsmntok_t *tok)
 bool json_tok_channel_id(const char *buffer, const jsmntok_t *tok,
 			 struct channel_id *cid);
 
+bool json_to_strarr(const tal_t *ctx, const char *buffer,
+		     const jsmntok_t *tok, const char ***arr);
+
 /* Guide is % for a token: each must be followed by JSON_SCAN().
  * Returns NULL on error (asserts() on bad guide). */
 const char *json_scan(const tal_t *ctx,

common/jsonrpc_paginator.h

@@ -2,12 +2,10 @@
  * Welcome in this wanderful experience of writing
  * a paginator for the core lightning JSON RPC 2.0 in C!
  *
- *
  * I will try to keep the code as simple as possible,
  * so if you had any dout on what I'm trying to do, blame me
  * that I was not able to do my job.
  *
- *
  * In short, the goal of this paginator is offer a struct
  * that it is used to grep the paginator information by
  * pre processin the JSON RPC request.
@@ -18,16 +16,14 @@
  * if the paginator will be enbaled on the listnodes, the
  * call will be
  *
- * cli | rest | grpc -> json_paginator_listnodes -> json_listnodes + struct jsonrpc_paginator -> sjon response { .... }
+ * cli | rest | grpc -> json_paginator_listnodes -> json_listnodes + struct jsonrpc_paginator -> jon response { .... }
  *
  * Done, this should be all!
- *
- *
- * Now let see how this is implemented.
- * */
+ */
 #ifndef JSONRPC_PAGINATOR_H
 #define JSONRPC_PAGINATOR_H
 
+#include <assert.h>
 #include <ccan/tal/tal.h>
 #include <ccan/short_types/short_types.h>
 
@@ -50,25 +46,27 @@
 struct jsonrpc_paginator {
 	/** reall usefult for access to gossip map */
 	const char **batch;
-	/** query the database */
+	/** query the database, for more complexy
+	 * query please use the sql plugins */
 	const u64 *offset;
 	const u64 *limit;
 	/* FIXME: more smarter one? like sort_by = "json key"
 	 * but this required to have a mapping between json_keys and sql keys
 	 * maybe we had already somethings in the sql plugin? */
 };
 
-/** new_paginator - helper function to create a new paginator from a list of parameter.
+/**
+ * new_paginator - helper function to create a new paginator from a list of parameter.
  * This is simple enought to be avoided, but write simple code inside the C macros
  * is frustating, so let use this insteand.
  *
  * BTW: I love C Macros, really!
- * */
+ */
 static inline struct jsonrpc_paginator *new_paginator(const tal_t *ctx, const char **batch,
 					      const u64 *limit, const u64 *offset)
 {
 	struct jsonrpc_paginator *paginator = NULL;
-	if (batch || limit || offset) {
+	if (batch || (limit && offset)) {
 		paginator = tal(ctx, struct jsonrpc_paginator);
 		paginator->batch = batch;
 		paginator->limit = limit;
@@ -77,5 +75,4 @@ static inline struct jsonrpc_paginator *new_paginator(const tal_t *ctx, const ch
 	}
 	return NULL;
 }
-
 #endif // JSONRPC_PAGINATOR_H

common/test/run-json_filter.c

@@ -72,6 +72,8 @@ const char *json_scan(const tal_t *ctx UNNEEDED,
 bool json_to_channel_id(const char *buffer UNNEEDED, const jsmntok_t *tok UNNEEDED,
 			struct channel_id *cid UNNEEDED)
 { fprintf(stderr, "json_to_channel_id called!\n"); abort(); }
+bool json_to_strarr(const tal_t *ctx UNNEEDED, const char *buffer UNNEEDED, const jsmntok_t *tok UNNEEDED, const char ***arr UNNEEDED)
+{ fprintf(stderr, "json_to_strarr called"); abort();}
 /* Generated stub for json_to_millionths */
 bool json_to_millionths(const char *buffer UNNEEDED, const jsmntok_t *tok UNNEEDED,
 			u64 *millionths UNNEEDED)

common/test/run-json_remove.c

@@ -133,6 +133,9 @@ bool json_to_txid(const char *buffer UNNEEDED, const jsmntok_t *tok UNNEEDED,
 bool json_to_u16(const char *buffer UNNEEDED, const jsmntok_t *tok UNNEEDED,
                  uint16_t *num UNNEEDED)
 { fprintf(stderr, "json_to_u16 called!\n"); abort(); }
+bool json_to_strarr(const tal_t *ctx UNNEEDED, const char *buffer UNNEEDED,
+		    const jsmntok_t *tok UNNEEDED, const char ***arr UNNEEDED)
+{ fprintf(stderr, "json_to_strarr called"); abort();}
 /* Generated stub for json_tok_bin_from_hex */
 u8 *json_tok_bin_from_hex(const tal_t *ctx UNNEEDED, const char *buffer UNNEEDED, const jsmntok_t *tok UNNEEDED)
 { fprintf(stderr, "json_tok_bin_from_hex called!\n"); abort(); }

plugins/libplugin.h

@@ -487,23 +487,4 @@ const jsmntok_t *jsonrpc_request_sync(const tal_t *ctx, struct plugin *plugin,
 				      const char *method,
 				      const struct json_out *params TAKES,
 				      const char **resp);
-
-#define PAGINATOR(callback)						                \
-	static struct command_result* callback##_paginator(struct command *cmd,         \
-	                                     const char *buffer,                        \
-	                                     const jsmntok_t *params)                   \
-	{                                                                               \
-		const char **batch;						        \
-		u64 *limit, *offset;                                                    \
-                if (!param(cmd, buffer, params,				                \
-	             p_opt("batch", param_arr_str, &batch),                             \
-                     p_opt("limit", param_u64, &limit),                                 \
-		     p_opt("offset", param_u64, &offset),                               \
-	             p_opt_any(),                                                       \
-		     NULL))                                                             \
-		     return command_param_failed();                                     \
-		cmd->paginator = new_paginator(cmd, batch, limit, offset);              \
-                return callback(cmd, buffer, params);				        \
-        }
-
 #endif /* LIGHTNING_PLUGINS_LIBPLUGIN_H */

plugins/topology.c

@@ -1,7 +1,3 @@
-#include "ccan/list/list.h"
-#include "ccan/strmap/strmap.h"
-#include "ccan/tal/tal.h"
-#include "common/node_id.h"
 #include "config.h"
 #include <assert.h>
 #include <ccan/array_size/array_size.h>
@@ -431,13 +427,13 @@ static bool node_in_paginator(struct command *cmd, struct node_id *node_id)
 			for (i = 0; i < tal_count(p->batch); i++) {
 				id = p->batch[i];
 				if (strcmp(id, target_id) == 0)
-					return true;
+					goto done;
 				plugin_log(cmd->plugin, LOG_DBG, "not match %s != %s", target_id, id);
 			}
 		}
 		return false;
 	}
-	tal_free(p);
+done:
 	return true;
 }
 
@@ -525,7 +521,7 @@ static struct command_result *json_listnodes(struct command *cmd,
 
 	if (!param(cmd, buffer, params,
 		   p_opt("id", param_node_id, &id),
-		   p_paginator(),
+		   p_paginator(&cmd->paginator),
 		   NULL))
 		return command_param_failed();
 
@@ -670,8 +666,6 @@ static const char *init(struct plugin *p,
 	return NULL;
 }
 
-PAGINATOR(json_listnodes);
-
 static const struct plugin_command commands[] = {
 	{
 		"getroute",
@@ -698,7 +692,7 @@ static const struct plugin_command commands[] = {
 		"network",
 		"List all known nodes in the network",
 		"Show node {id} (or all known nods, if not specified)",
-		json_listnodes_paginator,
+		json_listnodes,
 	},
 	{
 		"listincoming",